Veteran Thai journalist Panee (not her real name) has been sharing news through her Twitter account for the past four years, but she recently set up an anonymous account to evade monitoring by the ruling junta. And she only tweets using a proxy server, just to be doubly safe.

"I fear that if I use my old Twitter account freely, my posts may be used to harm me," she says.

Panee is among the many journalists, academics and activists who, after the May 22 military coup, sought security under the cloak of online anonymity in order to continue expressing their views without the risk of arrest.

Since taking power last month, junta chief Prayuth Chan-ocha has clamped down on criticism of the military as well as the coup, in what he calls a bid to restore "peace and order" after nearly seven months of political conflict.

While a curfew imposed after the coup is being lifted gradually in various parts of the country, censorship and surveillance of the Internet and social media remain.

Last week, police arrested Sombat Boonngamanong, a prominent organiser of anti-coup protests, by tracking him down through his IP address. They warned that they would go after people who post "divisive" political views online.

The surveillance has sent a chill through the kingdom's normally bustling online community, especially among individuals who do not agree with the military intervention. Adding to the climate of fear are reports that those detained have had the contents of their mobile phones searched for incriminating material.

In response, normally outspoken individuals have set up anonymous accounts on Facebook, Twitter, Line or other social media applications in order to avoid detection, and loaded up virtual private networks and secure chat lines.

Panee says: "Many of my friends created secret Twitter and Facebook accounts after the coup. Some just changed their names on Facebook, but many... set up new accounts to share their views."

Although she still tweets from her original account, she has "to do it under strict control and be careful about every word I use".

The self-censorship comes as a shock for designer Vajira Ruthiraknok, 43, who describes himself as politically neutral but dislikes former premier Thaksin Shinawatra. Thaksin, ousted in a military coup in 2006, was accused of exercising undue control over the country through his proxies in the past eight years. Many Thais who oppose Thaksin support the military intervention.

''If I don't like Thaksin, I can say it. If I don't like (opposition leader Abhisit Vejjajiva), I can say it. But if I don't like General Prayuth, I cannot say it,'' Vajira laments. ''What is this?''

He worries, too, about the increasingly aggressive tone among some of his pro-coup friends who, he says, are staging the equivalent of online witch-hunts against people who oppose the military.

''I came across a Facebook post once that said: 'Kill them. Chase them','' he recalls with a shudder.

Ask those who support the coup, however, and they would say the online censorship is a regrettable but necessary part of the political recovery as the junta prepares the ground for fresh elections in about 15 months.